1. Field
The embodiments described below relate generally to imaging using X-rays. More particularly, some embodiments concern two-dimensional imaging using a computed tomography scanner.
2. Description
Images of internal patient volumes are commonly used in modern medical practice. Such images may be used to generate or confirm a diagnosis and/or to plan a course of treatment.
In order to obtain an internal image, a patient is typically transferred to a facility (i.e., an “RF” room) providing radiographic/fluoroscopic imaging. The RF room includes one or more monolithic systems for obtaining two-dimensional (radiographic) images and/or two-dimensional+time (fluoroscopic) images. In some instances, these images may be sufficient for diagnosis, intervention, and treatment planning.
In other instances, the images obtained in the RF room may indicate a volume within the patient about which more information is desired. Accordingly, the patient may be moved to a three-dimensional imaging system located in another room or building. The three-dimensional imaging system may comprise a computed tomography (“CT”) system including an X-ray source and a radiation receiver that are mounted to face one another on opposite sides of a ring. The patient is positioned within the ring so that the volume of interest lies between the X-ray source and the radiation receiver. A three-dimensional image of the volume of interest is generated from two-dimensional projection images obtained by the receiver as the ring is rotated.
Two-dimensional images are initially acquired in the RF room for at least two reasons. First, the significant cost of obtaining a three-dimensional image may be avoided if the images acquired in the RF room are sufficient for their intended purpose. Second, high resolution two-dimensional images acquired in the RF room are frequently sufficient for the clinical task. It has been proposed to use two-dimensional projection images acquired by a CT scanner as an alternative to RF room images, but currently these projection images are not sufficiently detailed for most diagnosis and/or treatment planning.
Systems are desired that may reduce the need for separate RF and CT imaging systems.